Sampling or coring devices have been known in the past. Typical of devices for obtaining solid core samples are U.S. Pat. Nos. 4,317,490; 3,163,241; 4,356,872; 3,146,837; 1,784,886; 2,170,716; 3,064,742; 3,438,452; 4,081,040; 3,794,127; and 4,518,050. Specific techniques for coring and obtaining formation soil samples were also discussed in Society of Petroleum Engineers (SPE) paper 15385 by Whitebay, called "Improved Coring and Core-Handling Procedures for the Unconsolidated Sands of the Green Canyon Area, Gulf of Mexico," and SPE paper 14297 by Tibbitts and Radford, entitled "New Technology in Tools for Recovery of Representative Cores from Uncemented Sand Formations."
A variety of formation fluid sampling tools have been used in the past. Some of these tools are adaptable to also sample formation liquids. These tools include U.S. Pat. Nos. 2,382,992; 4,669,554; 4,310,057; 2,141,261; 4,350,051; 4,335,622; 4,804,050; 2,740,477; 3,139,147; and 4,807,707.
The apparatus of the present invention provides a simply constructed fluid sampling tool which is designed to accommodate fluid sampling from within the formation at a depth sufficient to preclude contamination of the fluid sample obtained with formation liquids.
The simple construction of the apparatus of the present invention facilitates its objective of obtaining undisturbed fluid samples. The apparatus does not require auxiliary devices to be inserted ahead of it into the formation prior to obtaining the fluid samples. The apparatus is also equipped with means to facilitate its rapid extraction.